PROJECT SUMMARY For adults with type 2 diabetes (T2D), daily performance of self-care behaviors improves glycemic control and prevents complications and premature mortality. However, sustained self-care remains highly challenging and high diabetes distress is common. Family members and friends can either reinforce or undermine patients? self-care, and many experience distress about not knowing how to best support the patient?s self-care efforts. Although engaging family/friend support persons may be a highly effective way to improve T2D outcomes, this has rarely been investigated. To address these problems, we developed FAMS, a mobile phone-delivered intervention including telephonic coaching focused on improving social support and self-care goals plus text message support for patients, and text messages for their adult support person. Our pilot study demonstrates that FAMS is acceptable, feasible, improves the support patients receive, and that it likely improves self-care. To move this promising line of research forward, we now propose the following specific aims: Aim 1: Expand and improve FAMS. We will build on our pilot study by: (a) expanding FAMS content beyond diet and physical activity to include regimen-tailored medication adherence strategies, (b) extending its interactive text message functionality to support persons, and (c) enhancing its goal-setting element by incorporating evidence-based diabetes education materials. This will be achieved through iterative user-centered testing to identify and resolve content, technical, research process and usability issues. Aim 2: Evaluate FAMS 2.0 effects on T2D patients? outcomes. We will conduct an RCT with 334 patient-support person dyads (~50% cohabitating) to evaluate the effects of the expanded FAMS 2.0 intervention versus an attention control (print materials on T2D self-care and access to A1c results) on long- term glycemic control (primary outcome) and psychosocial well-being (secondary outcome). Adults with T2D and baseline A1c>7.5% will be identified and recruited via the Mid-South Clinical Data Research Network and will enroll with a support person. We will oversample patients of racial/ethnic minority background or who have low socioeconomic status. Randomization will be performed within binomial strata defined by A1c and distress. The 15-month study timeline will consist of a 9-month intervention period with a 6-month follow-up to evaluate sustained effects. We will also assess key process measures including coaching fidelity and text message response rates. Aim 3: Explore FAMS 2.0 effects on support persons. We will evaluate whether support persons assigned to FAMS 2.0 experience greater improvements in their own support burden and psychosocial well-being than those assigned to control. Aim 4: Examine hypothesized moderators and mediators of the effects specified in Aims 2 and 3. We will evaluate whether effects on patients and their support persons vary by gender and dyadic cohabitation, and if improvements in targeted psychosocial and behavioral mechanisms mediate improvements in patients? and SPs? outcomes. Completion of this proposed research will establish whether this highly novel intervention improves outcomes among adults with T2D and their support persons, for whom, and through what mechanisms. It will also yield an inherently scalable intervention and a robust infrastructure to support subsequent implementation research.